My business partner disabled the ABS in his 96 Crown Vic to defeat the traction control that was tied into the ABS system. As said before, the ABS light was on the whole time but there was no other issues he had for the rest of the time he owned the car, which was around five years.
My 96 GT came from the factory without ABS. In the time I owned it, I made one panic stop and it was a hairy situation. It was a 60mph lockup entering an on-ramp when someone passed by me in the single lane at a very high speed. I had to brake to avoid rear-ending them and I must have slid for half the exit lane. Ruined my tires. If you do it, take the time to relearn the driving dynamics, especially if it's a sporty car that you're going to be driving in a sporty manner.